Territory



(No Model.)

G. WOOSTERQ ADJUSTABLE BRIDGE'POR STRINGED MUSICAL INSTRUMENTS N0.490,528. Patented Jan. 24, 1893.

% V429 i) ATTORNEYS.

as zithers, guitars, mandolins, and other in- UNITED STATES PATENTOFFICE.

GEORGE WOOSTER, OF FORT APACHE, ARIZONA TERRITORY.

ADJUSTABLE BRIDGE FOR STRINGED MUSICAL INSTRUMENTS.

$PECIFIGATION forming part of Letters Patent No. 490,528, dated January24, 1893.

Application filed October 17, 1892.

To all whom it may concern;

Be it known that I, GEORGE WOOSTER, of Fort Apache, in the county ofApache and Territory of Arizona, have invented a new and ImprovedAdjustable Bridge for Stringed Musical Instruments, of which thefollowing is a full, clear, and exact description.

My invention relates to an improvement in bridges for stringed musicalinstruments such struments having a fretted key-board; and the object ofthe invention is to so construct the bridge that the operator mayexpeditiously and conveniently adjust the string rests with reference tothe strings to render the latter accurate as to length and elevation.

Another object of the invention is to provide a bridge with string restsequal in number to the number of strings employed upon the instrument,and to provide for the independent adjustment of each of the rests.

The invention consists in the novel construction and combination of theseveral parts, as will be hereinafter fully set forth and pointed out inthe claims.

Reference is to be had to the accompanying drawings forming a part ofthis specification, in which similar figures and letters of referenceindicate corresponding parts in all the Views.

Figure 1 is a perspective View of a bridge mounted for use upon aguitar; Fig. 2 is a transverse vertical section through the entirebridge; Fig. 3 is a perspective View of the bridge plate; and Fig. 4 isa perspective View of one of the string rests and its attachments.

A foundation board A, is constructed of any desired shape and of anyapproved material. The said foundation board may, if desired, beconstructed of a light wood.

The foundation board is provided with an opening extending from top tobottom and ranging at equal distance from the center in direction ofboth of the ends, and into this opening the bridge plate B, is fittedand securely fastened by means of glue or other attaching medium. Thebridge plate is provided in its under surface with a series oftransverse channels 10; these channels extend through its forward edge,but not necessarily through the rear edge, and over each Serial No.449,140- (No model.)

channel a longitudinal slot 1l,is made in the bridge plate,communicating with the channel below it; and channels 12, are producedin the bottom of the foundation board, transversely thereof andextending through the forward edge, registering with the channels in thebridge plate. An anchor plate 13, is securely attached to the foundationboard at the rear of the bridge plate, and the anchor plate extendsupward beyond the foundation board, being provided with openings 14,corresponding in number and location to the.

slots in the bridge plate.

The strings 15 of the instrument are passed through the openings in theanchor plate and knotted or otherwise manipulated to prevent theirwithdrawal through the openings in which they are located. Each slot 11in the bridge plate is provided with a string rest 16. Each string restis made integral with or attached to a base plate 17, and beneath andparallel with the base plate a locking plate 18 is located, the base andlocking plates being spaced some distance apart and adjustably connectedby means of screws 19.

It will be understood that instead of using a locking plate 18 eachscrew may be provided at its lower end with a nut, and the width of thenut, if it is employed, and the width of the locking plate of eachstring rest, are such as to enable the plate or nut to fit properlyinone of the channels 10, and also to have sliding movement in thechannel. The upper face of the bridge plate is covered usually withchamois, or like material, as shown at 20 in the drawings, the chamoiscovering having slots therein corresponding to those in the bridgeplate.

In locating a string rest upon the bridge plate, the locking plates aremade to enter the channels 10; the base plate of a string rest is placedover each opening 11 in the bridge plate, and the adjusting screws ofthe base plates are passed downward through the latter and into itsparallel locking plate. Thus it will be observed, for example, that byscrewing upward the adjusting screws 19 the base plates and the lockingplates of the various string rests may be independently slidtransversely over the bridge plate, either toward or from the anchorplate, as occasion may demand and it is evident that each of the stringrests is independentof any of the others used upon the instrument, andthat the string rests may be rigidly held in the position in which theyare placed by tightening the screws 19.

The foundation board may be varied as to its shape, and the bridge plateand anchor plate may be and preferably are made from bone, ivory, or ofhard wood, while in the construction of the string rest and itsappendages metal is preferably employed.

The application of the bridge is as follows: WVhen mounted upon theinstrument, a zither, guitar or mandolin, for example, the strings aredrawn to the tension at which they are to be used; the string rests arethen moved backward or forward upon the bridge plate until the stringswhen pressed upon the twelfth fret give tones exactly one octave abovethe tones given by the open strings, or in unison with the harmonictones given by touching the strings over the said twelfth fret. Whenthus correctly placed the string rests are fastened firmly to the bridgeplate. A different elevation may be accomplished by using string restsof varying heights.

Among the many benefits that musicians may derive by the use of theabove described bridge may be named the following: The strings as soldfor instruments of the character heretofore named are of irregular sizeand elasticity, and this can be allowed for by the adjustment of thestring rests; the strings in a perfect set are of different sizes andare used at different tensions and they can not give perfect harmonyfrom the frets when strings thus varying in size and elasticity aregiven the same length; the musician can correct this by adjusting thestring rests to give a tense string a greater length than a lax one. Inthe class of instruments above enumerated different tunings are used,thus requiring a slightly difierent adjustment and in this emergency theadjustable string rests will accomplish that which the musician mayrequire.

It may here be remarked that as the vibrarests to the plate, as and forthe purpose set forth.

3. In a bridge for musical instruments, a bridge plate provided with aseries of string rests independently adjustable, each string rest havingan independent locking device, as and for the purpose specified.

4. In a bridge for musical instruments, the combination with a bridgeplate provided with channels on its under side and With boltscommunicating with the said channels, of string rests upon the bridgeplate over the slots thereof, locking plates in the channel of thebridge plate, and screws passing through the slots and connecting thestring rests and locking plates, substantially as described.

5. In a bridge for musical instruments, the combination with afoundation board having an opening therein and provided with an anchorplate, of a bridge plate fitted in the opening of the foundation boardand provided with grooves on its under side and with slots communicatingwith said grooves, string rests upon the bridge plate over the slotstherein, locking plates in the grooves of the bridge plate, and screwspassing through the slots of the bridge plate and connecting the stringrests and locking plates, substantially as herein shown and described.

GEORGE VVOOSTER.

Witnesses:

WILLIAM WoosTER, HOWARD IRVING.

